In recent years, a technique for compressing and recording image data and sound data has been advanced and practically applied. For example, the MPEG (Moving Picture Expert Group) method is used as a compression method of a high efficiency.
The applicant of the present application has formerly proposed a reproducing method in Japanese Patent Laid-open No. 2001-36412. For example, the method reproduces the recorded image data, at a variable speed including a twofold speed or more in the forward direction and a non-magnified speed or more in the reverse direction, from a recording medium in which image data interframe-compressed by a high efficiency coding method such as the MPEG2 are recorded by a helical scanning method, in the case that the track width of a magnetic head for recording and the width of a track to be recorded are equal to each other.
In the proposal, data for variable speed reproduction is discretely recorded at positions which are to be traced upon variable speed reproduction, and also the arrangement pattern wherein the data is recorded matches with the interleave. Consequently, data can be acquired with certainty upon variable speed reproduction, and matching between two kinds of regularity of image data for variable speed reproduction and the interleave can be established upon editing such as intermittent successive recording.
The above-mentioned proposal, however, has such problems as described below. In particular, if a magnetic tape is fed at a low speed when compared with a speed in a standard mode as in, for example, a long time mode to record data, then the crosstalk amount from a same azimuth track neighboring across one track increases and the number of sync blocks which can be acquired by one trace decreases, when compared with crosstalk amount and a number of sync blocks where a magnetic tape on which data is recorded in a standard mode is reproduced at a high variable speed. There is the possibility that a failure in acquisition of the data may occur, accordingly.
Further, the influence of a bend of a recording track arising from a recording apparatus or a reproduction apparatus, distortion of a trace upon reproduction, a displacement of the position of a recording track by jitters of velocity servo upon recording, a deviation of the feeding speed by jitters of position lock servo upon reproduction and so forth increases as the recording track width decreases with respect to the track width of the recording magnetic head. As a result, with a magnetic tape of a long time mode, an error of a trace with respect to a target position upon high speed reproduction occurs more significantly than with a magnetic tape of a standard mode, and there still is a subject that a failure in acquisition of the data may occur.